Reminiscent of the movie of the Washington State bridge collapse shown in
college physics class back in the day. But I was intrigued by the term "vortex
shedding" and couldn't help but wonder if it is related in some way to virus
shedding at the Wuhan Institute of Virology.
-----Original Message-----
From: Didi Pei <didi@xxxxxxxxxx>
To: pa64@xxxxxxxxxxxxx <pa64@xxxxxxxxxxxxx>
Sent: Fri, May 21, 2021 9:47 am
Subject: [pa64] Re: Bet they'll hire Pei Architects next time
#yiv3758656574 #yiv3758656574 -- _filtered {} _filtered {}#yiv3758656574
#yiv3758656574 p.yiv3758656574MsoNormal, #yiv3758656574
li.yiv3758656574MsoNormal, #yiv3758656574 div.yiv3758656574MsoNormal
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{}#yiv3758656574 div.yiv3758656574WordSection1 {}#yiv3758656574 All tall
buildings sway. The trick is to control it. We subject all tall building
designs to in-depth wind tunnel testing. The problem here was most likely what
we call vortex shedding wherein under rare circumstances oscillating winds can
create forces at the upper corners (which can be reduced by careful design)
resulting in vibrations. Sometimes we end up cutting or otherwise modifying
these important upper corners to reduce the vortex effect. Is that what you
were talking about? Chinese structural engineers are quite good, but this
phenomenon is more difficult to detect and requires experienced engineers
working with experienced wind tunnel testing. I don’t think this was a case of
cutting corners but more inexperience. This building was not very tall. BTW
there are certainly more tall buildings built in the last 20 years in China
than in rest of the world combined. From: pa64-bounce@xxxxxxxxxxxxx
<pa64-bounce@xxxxxxxxxxxxx>On Behalf Of dmarc-noreply@xxxxxxxxxxxxx
Sent: Thursday, May 20, 2021 9:34 PM
To: pa64@xxxxxxxxxxxxx
Subject: [pa64] Re: Bet they'll hire Pei Architects next time Office
building at 28 State in Boston used to sway in high wind. On top floor you
could see the chandelier sway way back and forth. Then you realized it was a
pendulum and the whole building was moving around it. Cross braced in gut rehab
in early 90s. Engineers are the key and China seems to cut important corners in
many of these buildings
-----Original Message-----
From: rhelkins <dmarc-noreply@xxxxxxxxxxxxx>
To: pa64@xxxxxxxxxxxxx <pa64@xxxxxxxxxxxxx>
Sent: Thu, May 20, 2021 12:33 pm
Subject: [pa64] Bet they'll hire Pei Architects next time State Department
Issues Warning After Chinese Skycraper Wobbles Violently In Mysterious Incident
| ZeroHedge
